Yes, RACKETED is a Scrabble word!

Letter values in Scrabble US: R 1, A 1, C 3, K 5, E 1, T 1, E 1, D 2.

Is it a valid word?

RACKETED is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

celebrate noisily, often indulging in drinking; engage in uproarious festivities
make loud and annoying noises
hit (a ball) with a racket

Also: make whoopie, make merry, make happy, whoop it up.